Hi,
I was cleaning the machine and I found something in the boiler. I can't find where it came from.
Anybody have idea what it is?

Its the small thing, look like a pin and have a tiny O-ring on it. You can see it in the picture at the bottom.
I suspect it came from anti vacuum valve. So I put a picture together to confirm if the valve is complete.

Thanks

Yes, it's your anti-vac valve. It had a tiny e-clip at the top of that pin that must have broken or come off. Same thing happened here: La Pavoni Europiccola Millennium - Grouphead Insert / Broken Water Pipe

You might find an e-clip (2mm shaft) at a hardware store, then stick the pin through the safety valve hole and put the clip on.

Thanks a lot!